Oh, there appear to be multiple ways of earning Extra Ball in the same Ball, too. You get a guaranteed Force lock hole Extra ball light if you can complete the Jedi Training - FPS laser deflection with light sabre!

I also got Extra Ball as a random reward from the EMPIRE reward for Chewbacca, although on another occasion his reward was to give the bonus-total score as if the ball had drained (confused me for a minute!), and another time it was just a cash-in total of 3.xm.

There was a third way I've already forgotten.

Might try and read the table rules later - I'm usually just impatient to get playing!